New methane study could affect fracking debate

A major study released today on one of the most important issues in the fracking debate gives at least a little ammunition to both sides.

Fracking for natural gas in the Marcellus Shale formation.

The study concludes that the federal government has seriously underestimated the amount of the greenhouse gas methane seeping into the atmosphere from oil and natural gas operations, as well as other sources.

And yet, the researchers also argue that the United States is still better off fueling its power plants with natural gas rather than coal, even if gas operations are leaking more methane than expected.

The researchers — from Stanford, Harvard, MIT and other institutions — estimate that the country’s methane emissions are probably about 50 percent higher than the Environmental Protection Agency believes. That’s important, because methane is a potent greenhouse gas, with 30 times the global warming potential of carbon dioxide.

It’s also the main component of natural gas, which the United States is producing in ever-greater amounts thanks to hydraulic fracturing. Utilities are relying more on gas and less on coal to fuel power plants. Fracking supporters see this switch as a blow against climate change, because gas emits about half as much carbon dioxide when burned as does coal. Pres. Obama often calls domestic natural gas the “bridge fuel” to a cleaner energy future.

Fracking opponents, however, have warned that methane leaking from fracked wells and other natural gas operations could cancel out all the global warming benefits of dumping coal. They’ve taken to calling gas the “bridge to nowhere.”

The new study, published in the journal Science, surveys roughly 20 years of research on methane emissions across the United States, including measurements taken at specific wells and air samples from high in the atmosphere. The government’s estimate of methane emissions could be off by as little as 25 percent or as much as 75 percent, said lead author Adam Brandt of Stanford University. The researchers’ best guess was 50 percent.

That bolsters the argument of fracking foes who have cast doubt on government and industry estimates of methane emissions.

But the researchers also found that methane leakage from fracking is almost certainly not the main reason why the federal emissions estimates are too low. It probably accounts for about 7 percent of the excess methane, researchers said.

“This is a lot of methane — it’s not trivial,” said Brandt, an assistant professor of energy resources engineering. “But this doesn’t appear to be the main contributor. The math just doesn’t work out.”

In addition, leakage from fracking and natural gas operations isn’t large enough to cancel out the benefits of dropping coal, researchers concluded.

“It appears that shifting from coal to natural gas, when analyzed over a 100 year global warming time scale, is going to be still significantly beneficial,” Brandt said.

Precisely what fracking supporters want to hear.

The researchers also found that within specific natural gas operations, much of the leakage can come from just a few pieces of equipment. It can be a pressure release valve stuck open, or a corrosion hole in a pipe, Brandt said. Developing cheap and easy ways for oil and gas companies to detect leaks could yield a big benefit.

“If they know where the leak is, they want to go fix it,” Brandt said. “It’s costing them money.”